Allocentric spatial navigation impairment in schizophrenic subject: A model-based study

Experimental studies revealed spatial navigation impairments in schizophrenic patients. Both human and animal subjects exhibited diminished navigation performances compared to control ones. In brain, hippocampus is believed to be more involved in navigation and memory. In the pathology of schizophrenia, neural mechanisms especially synaptic transmission of hippocampal neurons change and functionalities of hippocampus decline. In present paper we used a computational model of CA3 area in the hippocampus and showed how underlying impairments in neural mechanisms observed in schizophrenia lead to navigation problems. To show the effect of schizophrenia on the navigation impairment, we used the place field concept. Based on our simulation results, after inducing neuropathology of schizophrenia into the model, place fields encoded the spatial information with lower resolution. These results can explain mechanism underlying observed navigation impairment in schizophrenic patients.